Method of measuring the charge condition of galvanic energy sources and apparatus for carrying out this method

• US 3,906,329 A
• Filed: 08/27/1973
• Issued: 09/16/1975
• Est. Priority Date: 08/30/1972
• Status: Expired due to Term

• Current Assignee: Christian Bader
• Original Assignee: Christian Bader
• Inventors: Bader, Christian
• Primary Examiner(s): Miller, J. D.
• Assistant Examiner(s): Hickey, Robert J.
• Application Number:
  US05/391,774
• Time in Patent Office: 750 Days
• Field of Search: 320/37-40,43-45,48,14,35,36 324/29.5,76A
• US Class Current: 320/134
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method and apparatus for measuring the charge condition of galvanic energy sources by means of an integrating measuring device, in which the charging current or a magnitude proportional thereto is weighted with a factor dependent on the predetermined gassing voltage which changes with temperature and is matched in its timely behavior to the charging condition of the energy source, and possibly also by a factor dependent on the respective battery temperature and dependent of the charging condition, before it is fed to the integrating measuring device; the discharge current or a magnitude proportional thereto is thereby multiplied with a factor dependent on the respective battery temperature and subsequently is raised to the power with an exponent (1 + m) whose term m itself is variable as a function of the battery temperature before it is fed in its turn to the integrating measuring device.

Claims

1. A method for measuring the charge condition of galvanic energy sources by means of an integrating measuring device, comprising the steps of sensing the charging and discharging current providing a signal therefrom having a magnitude at least substantially proportional to the charging current and a signal having a magnitude at least substantially proportional to the discharge current, weighting the signal magnitude which is at least substantially proportional to the charging current with a charge factor dependent on the predetermined gassing voltage, which is variable with temperature, and matched in its timely behavior to the charge condition of the energy source before feeding it to the integrating measuring device, multiplying the signal magnitude at least substantially proportional to the discharge current with a factor dependent on the respective battery temperature and subsequently raising the thus multiplied signal magnitude to a power with an exponent formed by a sum of terms, whose one term itself is variable dependent on the battery temperature, before it is in turn fed to the integrating measuring device, weighting the signal magnitude at least substantially proportional to the charging current with a factor dependent on the respective battery temperature and dependent on the charge condition before it is fed to the integrating measuring device, and feeding the signal magnitude at least substantially proportional to the charging current reduced by the proportion of the gassing current which is dependent on the difference between the battery terminal voltage and the gassing voltage, as well as a signal magnitude proportional to the average value of the discharge current raised to the power having said exponent to the integrating measuring device.

2. A method according to claim 1, further comprising the step of feeding the magnitude at least substantial proportional to the portion of the charging current serving for the gas development to a further integrating measuring device.

3. A method according to claim 2, characterized by so controlling the charging current by an integrating control device that the temperature dependent gassing voltage can be exceeded only when the charging current lies below a value dangerous with respect to the gassing.

4. A method for measuring the charge condition of galvanic energy sources by means of an integrating measuring device, comprising the steps of sensing the charging and discharging current providing a signal therefrom having a magnitude at least substantially proportional to The charging current and a signal having a magnitude at least substantially proportional to the discharge current, weighting the signal magnitude which is at least substantially proportional to the charging current with a charge factor dependent on the predetermined gassing voltage, which is variable with temperature, and matched in its timely behavior to the charge condition of the energy source before feeding it to the integrating measuring device, multiplying the signal magnitude at least substantially proportional to the discharge current with a factor dependent on the respective battery temperature and subsequently raising the thus multiplied signal magnitude to a power with an exponent formed by a sum of terms, whose one term itself is variable dependent on the battery temperature, before it is in turn fed to the integrating measuring device, and feeding the signal magnitude at least substantially proportional to the charging current reduced by the proportion of the gassing current which is dependent on the difference between the battery terminal voltage and the gassing voltage, as well as a signal magnitude proportional to the average value of the discharge current raised to the power having said exponent to the integrating measuring device.

5. A method according to claim 4, further comprising the step of feeding the magnitude at least substantial proportional to the portion of the charging current serving for the gas development to a further integrating measuring device.

6. A method according to claim 5, characterized by so controlling the charging current by an integrating control device that the temperature dependent gassing voltage can be exceeded only when the charging current lies below a value dangerous with respect to the gassing.

7. A method according to claim 4, characterized in that said proportional magnitudes are the charging current and the discharge current.

8. A method for measuring the charge condition of galvanic energy sources by means of an integrating measuring device, comprising the steps of sensing the charging and discharging current providing a signal therefrom having a magnitude at least substantially proportional to the charging current and a signal having a magnitude at least substantially proportional to the discharge current, weighting the signal magnitude which is at least substantially proportional to the charging current with a charge factor dependent on the predetermined gassing voltage, which is variable with temperature, and matched in its timely behavior to the charge condition of the energy source before feeding it to the integrating measuring device, multiplying the signal magnitude at least substantially proportional to the discharge current with a factor dependent on the respective battery temperature and subsequently raising the thus multiplied signal magnitude to a power with an exponent formed by a sum of terms, whose one term itself is variable dependent on the battery temperature, before it is in turn fed to the integrating measuring device, and feeding the signal magnitude at least substantially proportional to the portion of the charging current serving for the gas development to a further integrating measuring device.

9. A method for measuring the charge condition of galvanic energy sources by means of an integrating measuring device, comprising the steps of sensing the charging and discharging current providing a signal therefrom having a magnitude at least substantially proportional to the charging current and a signal having a magnitude at least substantially proportional to the discharge current, weighting the signal magnitude which is at least substantially proportional to the charging current with a charge factor dependent on the predetermined gassing voltage, which is variable with temperature, and matched in its timely behavior to the charge condition of the energy source before feeding it to the integrating measuring device, multiplying the signal magnitude at least substantially proportional to The discharge current with a factor dependent on the respective battery temperature and subsequently raising the thus multiplied signal magnitude to a power with an exponent formed by a sum of terms, whose one term itself is variable dependent on the battery temperature, before it is in turn fed to the integrating measuring device, and controlling the charging current by an integrating control device so that the temperature dependent gassing voltage can be exceeded only when the charging current lies below a value dangerous with respect to the gassing.

10. An apparatus for measuring the charge condition of galvanic energy sources by an integrating measuring means, characterized by weighting means for weighting a magnitude at least substantially proportional to the charging current with a charge factor dependent on the predetermined gassing voltage, which changes with temperature, and matched in its timely behavior substantially to the charging behavior of the energy source, means for feeding the thus weighted magnitude to the integrating measuring means, multiplying means for multiplying a magnitude at least substantially proportional to the discharge current with a factor substantially dependent on the prevailing battery temperature, further means operatively connected with said multiplying means for raising the multiplied magnitude to a power having an exponent formed by a sum of terms, one of said terms being itself variable substantially as a function of the battery temperature, and connecting means operatively connected to the output of said further means for feeding the thus-modified magnitude to the integrating measuring means.

11. An apparatus according to claim 10, characterized by means for reducing the magnitude at least substantially proportional to the charging current by the portion of gassing current dependent on the difference between the battery terminal voltage and the gassing voltage, said further means being operable to raise the average value of the magnitude at least substantially proportional to the discharge current to the power with said exponent, and both said reduced magnitude as well as said average value of the discharge current raised to said exponent power being fed to said integrating measuring means.

12. An apparatus according to claim 11, characterized in that said proportional magnitudes are the reduced charging current as well as said average value raised to the power with said exponent.

13. An apparatus according to claim 11, characterized by means for feeding the magnitude at least substantially proportional to said portion of the charging current serving for the gas development to a further integrating measuring means.

14. An apparatus according to claim 13, characterized by an integrating control means for so controlling the charging current that the temperature-dependent gassing voltage can be exceeded only when the charging current lies below a value dangerous as regards gassing.

15. An apparatus according to claim 10, which comprises a voltage converter means converting the actual battery voltage into a proportional voltage, a voltage divider means whose one partial resistance has a negative temperature coefficient and includes a tap means at which a voltage can be picked up proportional to the permissive gassing voltage, an operational amplifier means connected as voltage comparator in which the voltage proportional to the actual battery voltage is adapted to be compared with the voltage proportional to the permissive gassing voltage, a negative feedback condenser means operatively connected between the output and input of the voltage comparator with the output thereof operatively connected with a transistor means, the output signal of said voltage comparator which acts on said transistor means being matched in its timely behavior to the charge condition of the energy source, a current converter means which converts the battery current into a proportional voltage and feeds the same to the input of an operational aMplifier means connected as proportional amplifier, means including said last-mentioned operational amplifier and a first negative feedback network means for multiplying the voltage proportional to the charging current with a substantially constant factor and for subsequently multiplying the voltage proportional to the charging current by way of the collector emitter circuit of the transistor means with a factor between zero and about one dependent on the output signal of the voltage comparator, means for feeding the thus-multiplied signal to the input of an operational amplifier means, further multiplying means including a second negative feedback network means having a resistance with a negative temperature coefficient for multiplying the voltage proportional to the discharge current with a factor substantially dependent on the battery temperature and for thereafter raising the thus-multiplied signal to a power with an exponential factor represented by a sum of terms by way of a parallel circuit including a resistor means with a voltage-dependent resistance, means for feeding the signal raised to said power to the input of the operational amplifier means which includes a circuit having resistor means and supplies an output current proportional to the sum of the input voltages to the integrating measuring means.

16. An apparatus according to claim 15, characterized in that the integrating measuring means includes a warning signalling means which produces a signal when the available battery capacity drops below a predetermined minimum value.

17. An apparatus according to claim 10, characterized by a first proportional difference amplifier means having a time delay means which forms from the magnitudes consisting of battery voltage and gassing voltage a magnitude at least substantially proportional to the difference voltage thereof, a function generator means operatively connected with said first difference amplifier means which produces from the difference voltage a magnitude proportional to the gassing current, a second proportional difference amplifier means operable to form by way of a first negative feedback network means a magnitude at least substantially proportional to the charging current, third proportional difference amplifier means for forming from the magnitude at least substantially proportional to the charging current as determined in the second proportional amplifier means and from the magnitude proportional to the gassing current a magnitude proportional to the difference thereof, means for feeding said magnitude proportional to the difference to the integrating measuring means, and means including the second proportional difference amplifier means and a second negative feedback network means connected thereto for raising the magnitude corresponding to the average discharge current as determined in the second proportional amplifier means by way of the second negative feedback network means to a power with said exponent before feeding the same to said integrating measuring means.

18. An apparatus according to claim 17, characterized in that the respective magnitude is fed to the measuring means by way of further stages.

19. An apparatus according to claim 17, characterized in that the magnitude proportional to the portion of the charging current serving for the gas development is fed to the input of an operational amplifier means which includes circuit means having resistance means for supplying an output current proportional to the input magnitude to a further integrating measuring means.

20. An apparatus according to claim 18, characterized in that the further integrating measuring means includes a warning signalling means which produces a signal when the electric charge corresponding to the entire gas development and representing a measure for the electrolyte quantity of the battery used up as a result of gassing exceeds a predetermined value.

21. An apparatus according to claim 20, characterized by an integral control means having an input and aN output, the magnitude proportional to the voltage difference of the battery terminal voltage and the gassing voltage being fed to said last-mentioned input while a magnitude proportional to the desired value of the charging current appears at the output thereof, charging current control means including current-limiting means operatively connected to said integral control means, said integral control means comparing at least magnitudes proportional to the desired value and actual value of charging current and for preparing the amplified difference magnitude as control magnitude for the control of a charging apparatus.

22. An apparatus according to claim 10, characterized by an integral control means having an input and an output, the magnitude proportional to the voltage difference of the battery terminal voltage and the gassing voltage being fed to said last-mentioned input while a magnitude proportional to the desired value of the charging current appears at the output thereof, charging current control means including current-limiting means operatively connected to said integral control means, said integral control means comparing at least magnitudes proportional to the desired value and actual value of charging current and for preparing the amplified difference magnitude as control magnitude for the control of a charging apparatus.

23. A method for measuring the charge condition of galvanic energy sources by means of an integrating measuring device, comprising the steps of sensing at least one of the charging current, the discharging current and battery temperature, providing a signal having a magnitude at least substantially proportional to the charging current and a signal having a magnitude at least substantially proportional to the discharging current, modifying the signal magnitude which is at least substantially proportional to the charging current by at least weighting the signal magnitude with a charge factor dependent on the predetermined gassing voltage, which is variable with temperature and matched in its timely behavior to the charged condition of the energy source before feeding the resultant signal magnitude to the integrating measuring device, modifying the signal magnitude which is at least substantially proportional to the discharging current by multiplying the signal magnitude with a factor dependent on the respective sensed battery temperature and subsequently raising the thus multiplied signal magnitude to a power with an exponent formed by a sum of terms, whose one term itself is variable dependent on the battery temperature, before the resultant signal magnitude is in turn fed to the integrating measuring device, and feeding the signal magnitude at least substantially proportional to the charging current which signal magnitude is modified by the proportion of the gassing current which is dependent on the difference between the battery terminal voltage and the gassing voltage, as well as the signal magnitude proportional to the discharge current raised to the power having the exponent to the integrating measuring device.

24. A method according to claim 23, characterized in that the proportional signal magnitudes are the charging current and the discharge current.